Today, imaging devices such as video cameras are frequently used for conducting surveillance or monitoring operations. For example, video cameras are commonplace in financial settings such as banks or casinos, where money changes hands in large amounts or at high rates of speed. Video cameras are also often used to monitor the arrival or departure of goods or services in warehouses, fulfillment centers or other like facilities, as well as the travels of persons or objects in locations such as airports, stadiums or other dense environments, or the flow of traffic on one or more sidewalks, roadways or highways.
When conducting surveillance or monitoring operations, video cameras may be aligned and configured to capture imaging data such as still or moving images of actions or events within their respective fields of view, and information regarding the captured imaging data or the observed actions or events may be configured and subjected to further analysis in order to identify aspects, elements or features of the content expressed therein. Such video cameras may be provided alone or in groups, and programmed to recognize when an action or event has occurred, such as when a frame-to-frame analysis of video imagery suggests that a predetermined threshold has been exceeded or that a predetermined condition has been satisfied, or otherwise implies that the action or the event has occurred based on information or data captured by the video cameras.
In dynamic environments such as transportation centers or fulfillment centers in which diverse collections of people, objects or machines enter and exit from such environments at regular or irregular times or on predictable or unpredictable schedules, it is difficult to determine which portions of a field of view of an imaging device should be kept in focus, e.g., by adjusting one or more lenses or other components to place such portions within a depth of field of the imaging device, at a given time. In particular, where an imaging device has a fixed orientation, or where the field of view of the imaging device includes large numbers of people, objects or machines that have varying sizes or shapes and travel at varying velocities, determining a person, an object or a machine on which the imaging device should be focused, and on which of the people, objects or machines the imaging device need not focus, may be exceptionally challenging.